The illustration is great, but unfortunately the logic in the text is flawed. When it comes to a simple change in leverage, you cannot get something for nothing. Whenever you lighten up the pedal effort by a change in geometry, you reduce the lift of the pressure plate from the disc and suffer from inadequate disengagement or less torque capacity in order to make up for the lighter pedal effort.

The real advantage to the pull type system is that the pressure plate is a lot more efficient. Because the pressure plate is loaded in one direction only (toward the transmission) and the diaphragm is supported closer to the clutch bolt flange, there is significantly less deflection (flex) which is basically wasted travel. Any time you reduce travel to accomplish the same clamp load and lift, you can take advantage of the better efficiency by reducing pedal effort or pedal stroke.